Soften gelatin in water. Combine cream and sugar in saucepan and heat just to a boil. Off heat, stir in softened gelatin until fully dissolved. Add buttermilk and vanilla. Divide among 8 molds (I use solo plastic cups — see the picture at the side — because of the interesting ridges, but any small mold will do.) Refrigerate at least four hours.

To serve, briefly dip molds in hot water and invert on serving plate. You may have to rap them sharply to get them to unmold. If they remain in the mold, put them back in the hot water for another ten seconds or so.